LOWEST RED SANDSTONE. 393 



geological treatises, and do not admit of being 

 detailed in this work. The peculiarities also 

 which distinguish the superior red sandstones, 

 will more properly be examined hereafter, under 

 the head of the upper sandstones, to which these 

 properly belong. It will be merely necessary to 

 remark, that as the term red has been given to 

 both these kinds of sandstone, and as this colour 

 forms a very conspicuous link of resemblance, 

 when there are, moreover, often present but very 

 slight shades of difference in other respects, it is 

 especially requisite for the student, to be on his 

 guard lest he pronounce a judgment from that 

 which must be considered an accidental, and not 

 a necessary, feature. Such terms too often concur 

 in biassing the views of observers, even of great 

 acuteness ; more particularly, when derived from 

 characters so striking and so obvious ; and were 

 it possible to change names long received, the 

 abolition of the term red sandstone, would go far 

 towards remedying an evil, of which every geolo- 

 gist must, at some time or other, have been fully 

 sensible. 



It must be left to the decision of geologists, 



